VP-4684-S1 Coupler Sleeve - for 6 to 6 spline coupling
This polyolefin sleeve is made to fit over the 68-4684 driveshaft coupling in the early Ford closed driveshaft applications (1937-48). The sleeve is placed over the coupling after installing the two coupling pins. A heat gun is used to shrink the sleeve tightly over the coupling. If the coupling pins ever break or come loose, the sleeve will prevent them from dropping out of the coupling during operation, thus stopping the pin from scraping against the inner portion of the driveshaft torque tube. The pins will remain in place, keeping the coupling from shifting front to rear.
NOTE: The coupling and the pins are NOT included with the sleeve kit.